Check valve for rectifying column



Jan. 7, 1958 c. A. HUGGINS ET AL 2,819,

CHECK VALVE FOR RECTIFYING COLUMN Filed May 11, 1955 CHECK VALVE FORRECTIFYING COLUMN Clitford Andrew Huggins and Griflin C. Thrift,Wichita,

Kano, assignors to Koch Engineering (Company, Wichita, Kane, acorporation of Kansas Application May 11, 1955, Serial No. 507,568

4 Claims. (Cl. 261-114) The present invention relates to an improvedcheck valve for use in rectifying columns or similar contact apparatus,and this application is a continuation-in-part of Huggins and Thriftco-pending application Serial No. 414,578, filed March 8, 1954, issuedNovember 27, 1956, as Patent No. 2,772,080.

In order to better appreciate the contribution of the present inventionto the art, the following background should be borne in mind. In thegas-liquid contact or rectification art, bubble plate towers and sieveplate towers have been extensively used in large-scale commercialoperations. It is well recognized by those skilled in the art that sieveplate towers operate satisfactorily only over limited ranges of vaporand liquid rates of flow if draining through plate perforations is to beavoided. In addition, sieve plates must be maintained in proper levelalignment at all times if efiicient operation is to be assured. Bubblecaps, because of their detailed construction, require frequent cleaningand have limited flexibility at high liquid-vapor ratios. As is the casewith sieve plates, the level positioning of the bubble plate isessential to insure efficient vapor-liquid contact. a

The check valve construction provided by this invention obviates theabove and other disadvantages found in sieve plate and bubble cap platetowers and operates at efiiciencies approximating those of a perforatedplate while retaining operating ranges exceeding those of bubble platesin the course of attaining the following objects.

It is an object of this invention to provide a check valve constructionwhich offers negligible resistance to the How of liquid across the platesurface thereby eliminating vapor maldistribution due to a hydraulicgradient.

It is another object of this invention to provide a check valveconstruction in which all parts may be readily fabricated from sheetmetal blanks.

It is a further object of this invention to provide a check valveconstruction whereby the highest velocity vapors of the gases passingtherethrough are directed horizontally rather than vertically, therebygreatly re ducing the caning difliculties prevalent in sieve plateoperation.

it is still another object of this invention to provide a check valveconstruction which is operable over an exceedingly wide range of columnconditions.

These and other objects will become more manifest from the description,the drawings, and the appended claims.

In one embodiment of the invention a check valve structure for use in arectifying column is provided which utilizes the peripheries of theapertures in the column plates as valve seats, and concave-convex discsas closure members. in the normal course of operation, gaseous pressurefrom beneath the plates lifts the discs from their seats. Retainingmeans are provided for each disc, limiting the upward travel thereof andassuring return of the disc to its seat. The retaining means comprises afour-posted spider aifixed to the tray. The spider is plate stamped andsuitably bent prior to being fixedly clinched to the bottom platesurface in a single stroke upsetting operation. The disc retaining meanspossesses a novel design which offers minimum resistance to the flow ofliquid across the plate surface in the normal course of columnoperation, as will hereinafter be explained in greater detail.

For a more complete understanding of this invention, reference will nowbe made to the drawings, wherein Figure 1 is a top plan view of thevalve members, which comprise the essence of this invention, arranged ona plate fragment;

Fig. 2 is a side, elevational view taken on the line 2-2 of Figure 1 andon a scale enlarged thereover;

Fig. 3 is a front, elevational view taken on line 3-3 of Figure l and ona scale enlarged thereover;

Fig. 4 is a transverse, sectional view taken on line i-4i of Figure 1and on a scale enlarged thereover;

Fig. 5 is a perspective view of the disc retaining component of theprovided valve structure;

Fig. 6 is a plan view of a sheet metal blank from which the retainingmeans illustrated in Pig. 5 is formed;

Fig. 7 is a top plan view of a modified form of disc retaining means;and

Fig. 8 is a side, elevational view of the embodiment illustrated in Fig.7.

The top plan view illustrated in Fig. 1 discloses the relationshipbetween a valve disc or closure member it) and a surmounted discretaining means 12. As will be more clearly seen in Fig. 4, the discseats for the valve discs 10 comprise peripheries M- of apertures whichare formed in a rectifying column plate or deck to. it will be furthernoted from Fig. 2 that the decks 16 have downwardly depending lipportions 13 which define the apertures through which vapors rise. It isapparent that the projecting lip portions 118 materially strengthen thedeck 16, preventing bending or buckling thereof. The vapors rise throughthe apertured decks and raise the disc members Elli from their seats 14,in the course of countercurrently contacting liquid which is flowingdownwardly through the column and transversely across the deck 16. Fourposts or leg members 2d of the retaining means 12 slidably engage theperiphery of each disc lid in the course of the latter members openingand closing movements. The upward extent of the disc travel is governedby the vertical height of the legs 2t) which extends from the decksurface to the juncture of the vertical legs Ell with angularly disposedarms 22. Upon cessation of the vapor flow, the discs 10 are guided totheir seats 14 on the deck to by the legs 26.

No gaskets are needed to effect a liquid seal and prevent downward flowof the liquid on the top surfaces of the decks through the deckapertures, since even at the lowest loadings vapor weeps up through anycrevice.

The facile and ready manner in which the disc retaining meansillustrated in Fig. 5 is formed may be appreciated by noting the sheetmetal blank illustrated in Fig. 6. The blank in Fig. 6 may. be readilystamped from sheet metal stock and bent along the dotted lines to formthe retaining means, illustrated in Figs. 1 through 4. After having bentthe blank of Fig. 6 into the retaining means configuration shown inperspective in Fig. 5, reduced terminal portions 24 of the legs 2419 areinserted in deck apertures 2d, illustrated in Fig. 1, and fixedlyclinched to the bottom deck surface by means of a simple upsettingoperation. Following the upsettiris. operation, the straight line endlimit of each terminal leg portion 24 will be deformed resulting in aterminal end limit having a V-shaped notch therein, such as isillustrated in Figs. 2 through 4, inclusive.

It is thus seen that the retaining means 112 may be readily andeconomically fabricated, as it comprises a unitary member which isreadily stamped from sheet metal stock and readily formed into the finalretaining means configuration. The attachment of the retaining means tothe deck 16 is accomplished in a single-stroke upsetting operation inwhich the four reduced terminal leg portions of the retaining means 12are fixedly clinched to the undersurface of the deck 16.

in the normal course of operation in a rectifying column utilizing thecheck valve construction provided by this invention, vapors rising frombelow enter apertures defined by the depending lip portions 18. The discclosure members iii are removed upwardly from their seats 14 andmaintained in the elevated position at the juncture in the retainingmeans between the vertical legs 20 and the angularly disposed arms 22.While in the elevated position, vapors rising from below impinge againstthe lower surface of the discs and are dispersed horizontally to risethrough the liquid positioned on the surface of the deck 16. It is animportant feature of the illustrated check valve construction that thehighest vapor velocity is directed horizontally rather than vertically.As a result of the horizontal dispersion of the rising vapors coning, orblowing dry, 21 difficulty prevalent in sieve plate operation, isgreatly reduced. it is thus apparent that high velocity in the risingvapors exists only at deck level, at which point the vapors aresubmerged in liquid. Be fore emerging from the top surface of the liquidpositioned on the upper surface of the deck 16, the vapors will befinely dispersed and evenly distributed, assuring uniform and eiiicicntvapor-liquid contact.

In the usual rectifying tower operation, the downwardly flowing liquidtravels from side to side in opposed directions on successive plates.When bubble plates are utilized, a definite hydrostatic head between theliquid entrance and exit to the plate is required to overcome theresistance set up by the cap arrangement across which the flowing liquidmust travel. As a result of this hydrostatic gradient, it may occur thatno vapor will pass through the bubble caps positioned near the liquidentrance to the plate. As a result, the rising vapors will be forced topass through the remaining caps resulting in overloading of these lattercaps and possible column flooding. However, utilizing the check valveconstruction presented since the maximum height of any portion of theprovided check valve is approximately one inch, negligible obstructionto liquid w across the deck surface exists. Consequently, any vapormaldistribution through the check valves arranged on the deck due to anyhydraulic gradient I is substantially nil.

Referring now, more particularly, to Fig. 3, it will be noted that theretaining means arms 22 connect the vertical supporting legs of theretaining means 12 to a centrally disposed channel-like bight portion 23which in the illustrated embodiment has a ceiling portion joiningopposed parallel wall portions. The channel. passageway 3%, defined bythe bight portion 23, is positioned parallel to the flow of fluid acrossthe deck surface 16. As a result, resistance to the liquid flow isconsiderably reduced and the column etliciency is increased.

Referring now to Figs. 7 and 8, a modified form of retaining means isillustrated in which the retaining means for a plurality of disc memberslid which are aligned on a. deck su "a may be fabricated from a singleintegral blank. Retaining means 32, illustrated in Figs. 7 and 8,comprises longitudinal bight portion 34 from which three retaining legmembers 36 depend for guiding the movement of each disc ill from itsseat.

It will also be appreciated that the longitudinal bight portion 34- alsodescribes a longitudinal passageway through which liquid may flow in thecourse of its movement across the tray surface, thereby maintainingresistance to fluid flow at a minimum. Three leg members 36 which guideeach disc Ml, illustrated in Figs. 7 and 8,

are connected to the longitudinal bight portion 34 by means of angularlydisposed arms 38. As is apparent from Fig. 7, only three legs are neededto adequately retain the disc 10 in proper engagement with its seat 14.The legs 36 are clinched to the undersurface of supporting deck 16 in amanner similar to that previously explained with reference to theretaining means 12.

It will be noted that, by forming the retaining means 12 so that the twovertical legs 26 farther from the liquid entrance to the deck 16 arehigher than the two leg members 2t closer to the liquid entrance, thedisc 10, in the raised position, will assume an angular position,whereby a greater vapor discharge will emerge from that portion of thevalve opening disposed toward the liquid discharge and of the deck 16.As a result of this greater vapor discharge at one valve end portion,the liquid which flows across the deck from the fluid entrance to thefluid exit of the plate will receive an added impetus and fiowthereacross will be assisted and accelerated. In addition, the discs 10may vary in weight on any given tray. Consequently, at low operatingloads uniform vapor distribu tion through the decks, even though they beinstalled out of level, is assured, since the discs 10 will uniformlyrise from their seats on the deck surface area despite the difference inliquid head on various deck portions. While these particular featuresare not shown in the drawings, they are presented in said co-pendingapplication Serial No. 414,578, new Patent No. 2,772,080.

It is thus apparent that a novel check valve construction for use in acontacting device has been provided which may be readily fabricated andwhich offers little resistance to fluid fiow across a deck surface sothat the presence of a hydraulic gradient is substantially nil. Thecheck valve may be constructed from any material resistant to theliquid-vapor components to be utilized therewith. In addition, theconstruction provided allows added impetus to be given to the flowingliquid if so desired. Furthermore, uniform vapor distribution may beassured at low loads even though the tray surface may be installed in anonlevel position. The check valve presented is extremely flexible andwill eificiently operate under greatly varying conditions. At low vaporloads, uniform distribution of the rising vapors through the checkvalves is assured and liquid runback or drainage through the deckapertures is obviated, since at the lowest loads vapor will weep upthrough any crevice regardless of the weir setting which regulates theheight of fluid on a plate surface. At high loadings, when the valves 10are removed from the seats and abut the juncture of the arms 22 and thevertical legs 26 of the retaining means, the deck function-s somewhatsimilarly to a bubble plate, save that no obstruction to liquid flowexists and the vertical vapor velocity is relatively low, above thecontacting zone, thereby adding to the efiiciency of the contactingengagement between the gas and the liquid.

It is apparent from the illustrated embodiments of this invention thatmany modifications may be made therein which will still remain withinthe ambit of the basic inventive concept herein presented. The inventionprovided is to be limited, therefore, only by the scope of the appendedclaims.

We claim:

1. A check valve construction for use in a rectifying tower having apredeterminately apertured plate across which liquid flows, comprising avalve seat formed integral with such plate, reciprocally movable closuremeans surmounted on said valve seat and removable therefrom by gaseouspressure exerted from beneath such plate, and retaining means limitingthe movement of said closure means from said seat, said retaining meanscomprising a spider member having a plurality of supporting posts, eachof said posts having a reduced terminal end portion insertable in aplate aperture, said end portions being of suflicient length to traversesuch plate thickness, converging arm members angularly disposed to saidposts, a channel portion joining said arm members, said channel portionhaving a passageway disposed parallel to the normal flow of fluid acrosssuch plate surface whereby fluid may flow therethrough and resistance tofluid flow across the plate surface is maintained at a minimum.

2. A check valve construction for use with an apertured rectifying towerplate across which liquid flows in the normal course of operationcomprising a concave-convex closure member liftable from the peripheryof one of such plate apertures by gaseous pressure exerted from beneathsuch plate, a unitary spider suitably affixed to such plate, said spidercomprising a plurality of post members equispaced about one of suchplate apertures, transverse arm members angularly disposed to said postmembers, a channel portion joining said arm members, said channelportion having a substantially inverted U-shaped cross sectionalconfiguration, said channel being positioned in a plane parallel to theflow of liquid across such plate whereby a minimum of resistance will bepresented by said valve to said liquid flow.

3. Retaining means for a check valve adapted for use with a rectifyingtower plate across which liquid flows in the normal course of operation,said retaining means comprising a plurality of posts adapted forsupporting said retaining means and securing the same to such plate onwhich positioned, retaining means arm portions angularly disposed toeach of said posts, a channel comprising two parallel walls joined by aconnecting channel ceiling portion, said arm members engaging theopposed wall portions of said channel, said retaining means beingdisposed on such rectifying tower plate so as to be disposed parallel tothe flow of liquid thereacross whereby such fluid may flow between theopposed walls of said channel and the resistance to the flow of fluidacross such plate afforded by said retaining means is maintained at aminimum.

4. A check valve construction for use in a rectifying tower having apredeterminately apertured plate across which liquid flows, comprising avalve seat formed integrally with such plate, reciprocally movableclosure means surmounted on said valve seat and removable there from bygaseous pressure exerted from beneath such plate, and retaining meanslimiting the movement of said closure means from said seat, saidretaining means comprising a spider member having a plurality ofsupporting posts, each of said posts having a reduced terminal endportion insertable in a plate aperture, said end portions being ofsufiicient length to traverse such plate thickness, converging armmembers angularly disposed to said posts, a channel portion joining saidarm members, said channel portion comprising an elongate passageway ofuniform cross section, said passageway being disposed parallel to thenormal flow of liquid across said plate surface whereby liquid may flowtherethrough and resistance to liquid flow across the plate surface ismaintained at a minimum.

References Cited in the file of this patent UNITED STATES PATENTS1,047,807 Hine Dec. 17, 1912 2,016,390 Richardson Oct. 8, 1935 2,428,889Nutter Oct. 14, 1947 2,622,615 Golden et al -1 Dec. 23, 1952 2,649,277Blackford Aug. 18, 1953 2,718,900 Nutter Sept. 27, 1955 FOREIGN PATENTS619,029 France Dec. 23, 1926

